Traditionally the week of prayer is celebrated between 18-25 January, between the feasts of St Peter and St Paul. In the southern hemisphere, where January is a vacation time, churches often find other days to celebrate it, for example around Pentecost, which is also a symbolic date for unity.
In order to prepare for the annual celebration, ecumenical partners in a particular region are invited to produce a basic liturgical text on a biblical theme. Then an international editorial team of WCC and Roman Catholic representatives refines this text to ensure that it can be prayed throughout the world, and to link it with the search for the visible unity of the church.
The text is jointly published by the Pontifical Council for Promoting Christian Unityand the WCC, through the WCC’s Commission on Faith and Order, which also accompanies the entire production process of the text. The final material is sent to WCC member churches and Roman Catholic episcopal conferences, and they are invited to translate the text and contextualize or adapt it for their own use.
(Source: Tony Richie, World Council of Churches)